Beyond the tourist fantasy of the Louvre and the Eiffel Tower, France today is a fabulously colourful mixture of Christians, Muslims, Jews, Buddhists, Hindus, atheists. This is the situation all over Europe. Yet many Europeans are deeply uneasy with this diversity.

Yet media and government often still refer to Muslims as “them”: tolerated foreigners, immigrants graciously accorded rights by the state. And Muslims often respond by considering themselves unwanted outsiders, even enemies.

Until the Second World War, many believed that Jews could not be French. That lie was at the heart of the Dreyfus Affair that tore the country in two. Under the Nazi occupation, millions of Jews were arrested across Europe and sent to their deaths. Since the 1980s, France has come to terms with the ugly truth about its role in those deportations. When it comes to Islam, however, many Europeans still suffer from historical amnesia.

Most French people forget that Algeria was part of France for 130 years. They are unaware that the current Republic was born out of the bitter struggle over Algerian independence. France’s colonial domination extended through Asia, Africa, the Caribbean and the Pacific, but its heart was in the Muslim lands. Algeria became an integral territory of France after the Revolution of 1848.

In that year French men were the first to gain universal suffrage. Muslims, however, were excluded from voting for almost a century. Only after 1945 could Muslim men vote, along with French women. It took another 13 years for Muslim women to gain that basic right.

The Fourth Republic collapsed in 1958, when settlers fighting to keep Algeria French carried out a wave of terrorist attacks across France, culminating in an attempted coup d’état. Wartime leader Charles de Gaulle was hurriedly recalled and given emergency powers.

Against violent settler opposition, de Gaulle signed Algeria’s independence in 1962. A million European settlers, along with hundreds of thousands of Algerians, crossed the Mediterranean to France. French companies kept their lucrative interests in petroleum and mining. The two countries remained indissolubly linked.

Yet after decolonisation, most French citizens simply erased the colonies like a bad dream. Algerians could not do the same. In the 1990s, things turned nasty after the secular, French-backed regime in Algiers annulled elections won by an Islamist party. A bloody civil war broke out, killing more than 100,000 people. For Algerians in France, this horror left trauma, distrust and anger.

In 1995, the violence hit France when a bomb in the Paris subway left eight people dead. The atrocity ramped up French support for the authoritarian Algerian regime’s “war on terror”.

At home, the Muslim headscarf was increasingly targeted as a dangerous symbol of defiance against French secularism. The authorities banned the hijab in public schools, and made face covering in public illegal. Women wearing facial veils could be arrested in the street, forced to undergo searches, or pay fines. Rather than promoting secular freedoms, these laws fanned extremism, and pushed Muslims further to the margins.

A position once associated with the far-right, denouncing the loss of “French identity”, has now moved into the centre, where even elements of the former Left have joined it. The French values trumpeted by this republican fundamentalism are abstractions that have little connection to the reality of French society. Freedom of speech is one of these.

Right-wingers and libertarians alike enthusiastically applauded Charlie Hebdo’s bravery for publishing cartoons offensive to Muslims. Yet it is not clear what they were actually meant to achieve. To insist on abstract principle over negotiation, respect and compromise is what we usually think of as fanaticism.

Leaders of the fascist-leaning Front National (FN), eager to profit from the potential backlash, now mourn a magazine that consistently reviled them. Je suis Charlie, agreed former leader Jean-Marie Le Pen – adding that he meant Charles Martel, who expelled Muslims from France in the Middle Ages.

The attackers, French citizens of Algerian descent, also saw things in black and white. Their Islamist beliefs were built on a violent rejection of difference, a refusal to tolerate disagreement, dissent and compromise. This virulent religious nationalism is a mirror of movements like FN that rely on fear of Islam to build their constituency.

But all is not lost. Asked what he was thinking during the minute of silence for the victims, one man said he was staring at the words on the column before him. Liberty, Equality, Fraternity.

These are not French values. They belong to everyone. They are not easy, nor are they unstained by violence. Heads on pikes, the guillotine, wars, revolutions: it took a century of struggle for French people to agree on these words. They were almost lost in the brutality of colonial oppression, in the dark years of the German occupation and the anti-Semitism that some French people – including, sadly, many Muslims—perpetuate even today.

We must confront the past in its richness and its ugliness. France has never been the postcard fantasy of cheese and baguettes. There have always been Muslims, Jews and Christians in France. As one Muslim wrote during the French Revolution:

No matter where I first drew breath, or the religion in which I was born, we are brothers.

Many Muslims feel the same today.

Of liberty, equality and fraternity, the last is the biggest challenge. It is not just an idea but a way of life with deep roots in the French tradition. It is equally familiar in Islam. Fraternity is more than solidarity. It asks us to engage in the difficult project of living together, not as “us” and “them”, not in black and white, but in celebration of the vibrant colour that is Europe today.